Apparatus for use in the distribution of electric currents.



G. BERRY.

APPARATUS FOR USE IN THE DISTRIBUTION OF ELECTRIC GURRENTS.

APPLIOATION FILED MAY 6, 1911,

1,009,636, Patented N0v.21, 1911.

2 VIM/M W/tnesses: A? [/63 7 tor UNITED STATES PATENT OFFICE.

GEORGE BERRY, OF WEST DRAYTON, ENGLAND, ASSIGNOR T0 GENERAL ELECTRICCOMPANY, A CORPORATION OF NEW'YORK.

APPARATUS FOR USE IN THE DISTRIBUTION 013 ELECTRIC CURRENTS.

To all whom it may concern Be it known that I, GEORGE BERRY, a subjectof the King of Great Britain, residing at Colne Mead, town of WestDrayton, county of Middlesex, England, have invented certain new anduseful Improvements in Apparatus for Use in the Distribution of ElectricCurrents, of which the following is a specification.

My invention relates to apparatus for use in the distribution ofelectric currents wherein two transformers, namely, a main transformerand a spare transformer, with an auxiliary transformer, connected inseries with the spare transformer, are connected in parallel across asystem, and has for its object an improvement in such devices.

It has been proposed in the 'past to connect a main transformer, withits primary and secondary windings connected across supply anddistributing mains, in parallel with a spare transformer having itsprimary and secondary windings connected in series respectively with thesimilar windings of a small auxiliary transformer, these windingsconnected in series being connected 1n parallel to those of the maintransformer across the mains, and, by the use of a double actingelectromagnetic device havshort circuit the windings of thesupplementary transformer when the load exceeds a predetermined valueand to open the short circuits and put the spare transformerout ofeffective use when the load fallsbelow a predetermifiad value, thecircuit of each winding, after being closed at one point by the relay,being again immediately opened at another point by a switch operatedfrom a movable part of the electromagnetic device or the switchmechanism. Heretofore, the two windings of the electromagnetic devicehave been arranged to be connected by the relay'directly' across thesecondary mains with the result that should the main transformer failwhile the spare transformer is out of effective use, that is to say,during times of lowload, the'spare transformer which would then bebrought into use by the automatic ,short cireuiting of the supplementarytransformer windings, due to the momentary increase of current throughthe relay, due to the failure of the main Specification of LettersPatent.

Application filed May 6, 1911.

Serial No. 625,508.

the switch mechanism after acting automatically to short circuit thesupplementary transformer upon failure of the main transformer, duringtime of low load, from being afterward automatically moved into aposition to open the short circuit upon the relay, reassuming theposition corresponding to low load. I accomplish this object by anespecial arrangement of connections whereby the circuit for theelectromagnetic device adapted to open the short circuits about thewindings of the supplementary transformers will be opened or renderednon-effective upon failure of the main transformer.

The further novelties of my invention are pointed out with moreparticularity in. the claims appended to and forming a part of thisspecification.

For a further. understanding of my invention, reference may be had tothe accompanying drawing which shows diagrammatically the arrangement ofconnections which I may employ.

1 and2 are the primary supply mains connected to a suitable sourceof'electric energy that has not been shown.

3 and 4 are the secondary distributing mains supplying suitabletransforming devices which also have not been shown. The maintransformer T has its primary winding 5 and secondary Winding 6connected respectively across the supply and the distributing mains,respectively through circuit opening devices or fuses 7, 8.

9 and 10 are the primary and secondary windings of the spare transformerT connected in series respectively with the primary and secondarywindings 11- and 12 of the small supplementary transformer t andrespectively across the supply and distributing mains.

13 and 14 are the fuses for the primary and secondary windingsrespectively of the spare Patented Nov. 21, 1911.

fication of British Letters Patent No. 2096' of 1904, and comprising awinding 21 connected in, series with the primary main 1 ant. having itscore or armature 22 connected to a loaded lever 23 adapted to close thecircuit of winding 17 through fixed and movable contacts 24 and 25 andof winding 18 through the fixed and movable contacts 26 and 27.

'Ihe electromagnetic device shown is of the kind described in thespecification of British Letters Patent No. 8927 of 1905 and comprises amovable core 28 carrying armatures 29, 30 and the movable contacts 31and 32 of high and low tension switches respectively arranged to co-actwith the corresponding fixed contacts 33 and 34 of these 25 switches,and a supplementary switch comprising a movable contact 37 in the formof a lever fastened to the core 28 so as to be operated therefrom andfixed contacts 38, 39 connected to one end of the windings 17 and 18respectively, the other ends of these windings being respectivelyconnected to the relay contacts 24 and 28. In this arrangement,according to the invention the relay lever 23 and the switch lever 37are respectively connected by conductors 40 and 41 to the conductors 42and 43 by which the secondar windin 6 of the main trans- V former T isconnected to the secondary mains, the points of connection between theco conductors 40, 42 and 41, 43 being between the said secondary winding6 and the fuses 8 therefor. The levers 23 and 37 are also connecteddirectly to the distributing mains 3 and 4. Fuses 7 and 8 for the maintransformer are weaker than those, 13, 14, for the spare transformer, orthey are time fuses adapted to act in less time than those for the sparetransformer.

By the arrangement described, it will be seen that should the maintransformer T fail, the relay will be operated by the temporary increaseof current in the supply mains 1, 2 to cause the relay lever 23 to closethe circuit of winding 17 across the distributing mains 3, 4, energizethe closing winding of the electromagnetic device and cause it to closethe high and low tension switches 31-33 and 32--34, therefore shortcircuiting the supplementary transformer wind- 6 ings 11, 12 andbringing the spare transformer windings 9, 10 into effective use tosupply the distributing mains 3, 4. Upon the current in the supply mainsafterward falling below the predetermined value at which thesupplementary transformer is under normal conditions open circuited, itwill be seen that although the circuit of the winding 18 will be closedbetween contacts 26, 27 and contacts 37, 39, the said winding cannot beenergized to operate the switch mechanism to open the short circuit andput the spare transformer out of QlI QC/LIE use, because the maintransformer, owing to its failure and the blowing of one or the other ofits fuses, cannot supply current to the said winding.

Means, such as a weight 44, supported by a thread 45'carried by fusewire 46 in a circuit 47 that can be closed by one or the other of twosuspended circuit closing bars 48 controlled by the fuses 15 connectedto the primary winding 11 of the supplementary transformer, are or maybe provided as described in the said former specification of BritishLetters Patent No. 2096 of 1904 for causing the relay lever 23 toautomatically move into a position to cause the switch mechanism toshort circuit the supplementary transformer windings and keep them shortcircuited should either of the said fuses or the supplementarytransformer windings 11, 12 fail.

While I have described a preferred embodiment of my invention, I do notlimit myself to this embodiment, but seek in the appended claims tocover all embodiments which shall be obvious to those skilled in the artand not depart from the spirit of my invention.

What I claim as new and desire to secure by Letters Patent of the UnitedStates, is,

1. In an alternating current distribution system, supply anddistributing mains, a main transformer having its windings con nectedacross these conductors, a spare 1 transformer, and a supplementarytransformer, the primary and secondary windings of said transformersnormally connected respectively inseries and across said mains, anelectromagnetic device having windings adapted when energized to shortcircuit and open circuit the windings of the supplementary transformer,a relay in operative relation with the windings of said device, andmeans in operative relation with the relay causing the opening windingof said device to be rendered non-eifective upon failure of the maintransformer.

2. In an alternating current distribution system, supply anddistributing mains, a main transformer having its primary windingconnected across the supply mains, con nections between the secondarywinding of said transformer and the distributing mains,

a spare transformer, and a supplementary transformer, the primary andsecondary windings of said transformers normally connected respectivelyin series and across said mains, an electromagnetic device havingwindings adapted when energized to shortcircuit and open circuit thewindings of the supplementary transformer, a relay in operative relationwith said windings, and connections between the relay and the conductorsconnecting the secondary winding of the main'transformer and thedistributing mains adapted to render inoperative the opening winding ofthe electromagnetic device upon failure of the main transformer.

3. In an alternating current distribution system, supply anddistributing mains, a main transformer having its rimary windingconnected across the supp y mains, connections between the secondarwinding of said transformer and the distri utin mains, circuit openingdevices in series with said conductors, a spare transformer, and a slipplementary transformer, the primary and secondary windings of saidtransformers normally connected respectively in series and across-saidmains, an electromagnetic device having closing and opening windingsadapted when energized to short cirlation with said connections an cuitand open circuit the windings of the supplementary transformer,connections for energizing the closing winding from the secondary mains,connections for energizing the opening windin from the conductorsconnecting the distrlbuting mains and the secondary winding of the maintransformer intermediate its terminals and the circuit opening devices,and a relay in o erative rethe windings of the electromagnetic devicesada ted when the load exceeds a redetermined value to complete thecircuit or the closing winding of said device and when the load fallsbelow a redetermined value to complete the circuit for the openingwinding.

In witness whereof, I' have hereunto set my hand this twenty-fifth dayof April,

GEORGE BERRY,

Witnesses:

J C. WRIST,

MAUBIQE A. V. LONDON.

